CVE-2017-5963 in TYPO3
Summary
by MITRE
An issue was discovered in caddy (for TYPO3) before 7.2.10. The vulnerability exists due to insufficient filtration of user-supplied data in the "paymillToken" HTTP POST parameter passed to the "caddy/Resources/Public/JavaScript/e-payment/paymill/api/php/payment.php" URL. An attacker could execute arbitrary HTML and script code in a browser in the context of the vulnerable website.
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Analysis
by VulDB Data Team • 11/14/2022
The vulnerability identified as CVE-2017-5963 affects the caddy component within TYPO3 CMS versions prior to 7.2.10, representing a critical cross-site scripting flaw that stems from inadequate input validation mechanisms. This security weakness specifically manifests in the payment processing module where the "paymillToken" HTTP POST parameter fails to undergo proper sanitization before being processed and returned to users. The flaw exists within the file structure at caddy/Resources/Public/JavaScript/e-payment/paymill/api/php/payment.php, indicating a server-side script that directly incorporates user-supplied data without appropriate security measures. The vulnerability classification aligns with CWE-79 which describes improper neutralization of input during web page generation, commonly known as cross-site scripting attacks.
The technical implementation of this vulnerability allows an attacker to inject malicious scripts through the "paymillToken" parameter, which then gets executed within the browser context of legitimate users interacting with the vulnerable website. When the payment processing script receives the POST request containing the unsanitized token data, it fails to properly escape or validate the input before rendering it in the web page response. This creates an environment where attacker-controlled content can be executed with the privileges and context of the affected website, potentially enabling session hijacking, credential theft, or unauthorized transactions. The attack vector specifically targets the payment processing functionality, making it particularly dangerous for e-commerce environments where sensitive financial data is handled.
The operational impact of this vulnerability extends beyond simple script execution, as it can lead to complete compromise of user sessions and potential financial fraud. Attackers can leverage this weakness to inject malicious code that persists across user sessions, allowing for prolonged unauthorized access to the website's functionality. The vulnerability affects the entire TYPO3 ecosystem where caddy is implemented, potentially compromising numerous websites that have not updated to version 7.2.10 or later. This type of vulnerability also aligns with ATT&CK technique T1566 which involves social engineering through malicious code injection, and T1059 which covers command and scripting interpreter usage for code execution.
Mitigation strategies for CVE-2017-5963 require immediate implementation of input validation and output encoding mechanisms within the affected payment processing script. Organizations should ensure that all user-supplied data, particularly parameters used in web page generation, undergo proper sanitization before being processed or returned to users. The recommended fix involves implementing strict input validation for the "paymillToken" parameter and applying appropriate HTML escaping techniques to prevent script execution. Security practitioners should also consider implementing Content Security Policy headers to add additional layers of protection against script injection attacks. Regular security updates and patch management processes are essential to prevent similar vulnerabilities from being exploited in the future, as outlined in industry best practices for web application security maintenance and vulnerability remediation.